Fig. 8. DC provision of OX40L is redundant for efficient effector CD4 T cell responses to Salmonella typhimurium-2W1S.

To investigate the role of OX40L signals in other Th1 infection models, GS, GS × Rorc^cre × OX40L^f/f, GS × CD11c^cre × OX40L^f/f and GS × OX40^−/− × CD30^−/+ reporter mice were infected with intestinal pathogen Salmonella-2W1S via oral gavage 24 h post administration of streptomycin and the responses in the colon and mLN were assessed 7 days later. a Flow cytometric plots showing 2W1S-specific CD44^hi CD4 T cell response and the eYFP expression in the colon of GS, GS × Rorc^cre × OX40L^f/f, GS × CD11c^cre × OX40L^f/f and GS × OX40^−/− × CD30^−/+ mice at D7 post infection. b Enumeration of CD4 T cells in the colon. c Enumeration of 2W1S-specific CD4 T cells in colon. d Enumeration of eYFP⁺ 2W1S-specific CD4 T cells. e Percentage of 2W1S-specific CD4 T cells expressing eYFP. f Flow cytometric plots showing 2W1S-specific CD44^hi CD4 T cell response and the eYFP expression in the mesenteric LN of GS, GS × Rorc^cre × OX40L^f/f, GS × CD11c^cre × OX40L^f/f and GS × OX40^−/− × CD30^−/+ mice at D7 post infection. g Enumeration of 2W1S-specific CD4 T cells in the mesenteric LN. h Enumeration of eYFP⁺ 2W1S-specific CD4 T cells. i Percentage of 2W1S-specific CD4 T cells expressing eYFP. Data were pooled from 3 independent experiments (n = 8 GS mice, n = 15 GS × Rorc^cre × OX40L^f/f mice, n = 11 GS × CD11c^cre × OX40L^f/f mice, n = 6 GS × OX40^−/− × CD30^−/+ mice). Values on flow cytometric plots represent percentages; bars on scatter plots represents the median. Statistical significance was tested by using Kruskal–Wallis one-way ANOVA with post hoc Dunn’s test: *p ≤ 0.05, **p ≤ 0.01.